Caves of the ‘Star Man’: Homo naledi

New species of archaic humans seem to pop up pretty frequently these days. If you accept the evolution by natural selection model, then the human lineage is less of a linear progression from primate ancestors, and more of a messy demolition derby of sub-species which came and went, branching out into dead-end alleys of development. Only one line survived the ravages of the last few hundred thousand years – us. The remains of the rest, the human species which didn’t make it and succumbed to extinction, like Homo floresiensis, are being dug out of caves around the world.

The latest of these discoveries are the Homo naledi hominins, who appear to have lived in southern Africa some 300,000 years ago around the same time that early humans were emerging as a species (1). The remains of these hominins was discovered in the complex Rising Star system of caves in South Africa a couple of years ago (2). The bones littered a pit-like chamber which was very difficult to access. The bones provide palaeontologists with a curious set of archaic specimens. The small skull size of Homo naledi, providing space for a brain just half the size of a modern human, indicated a primitive hominin.

The small brain size led the palaeontology team, led by the maverick academic Lee Berger, of Johannesburg’s University of the Witwatersrand, to conclude that the species had lived perhaps 2 – 3 million years ago. The shape of the skull was suggestive of early Homo species, including Homo erectus, Homo habilis or Homo rudolfensis. However, various aspects of the skeleton more closely resembled modern humans – their wrists, the feet, the lower part of the pelvis, some of their teeth (3). It’s a very odd mix indeed:

““You could almost draw a line through the hips—primitive above, modern below,” said Steve Churchill, a paleontologist from Duke University. “If you’d found the foot by itself, you’d think some Bushman had died.”” (2)

Then there was the conclusion that the bones had been deliberately buried in this intricate cave system (after all other possibilities had seemingly been eliminated). Burying the dead is a practice thought to only be carried out by humans. So, Homo naledi offered the researchers a bizarre mix of human-like practices and skeletal structure, combined with various very primitive hominin characteristics. In evolutionary terms, this hominin hybrid did not fit into any recognised structure at all:

“In some ways the new hominin from Rising Star was even closer to modern humans than Homo erectus is. To Berger and his team, it clearly belonged in the Homo genus, but it was unlike any other member. They had no choice but to name a new species. They called it Homo naledi (pronounced na-LED-ee), tipping a hat to the cave where the bones had been found: In the local Sotho language, naledi means “star.”” (2)

So, the given scientific name of this hybrid creature literally means ‘star man’ (‘Homo’ is Latin for ‘man’, ‘Naledi’ is Sotho for ‘star’). Honestly, I’m not making this up!

Anyway, it was clearly vital to date these skeletal remains. Were they ancient hominins, like Homo erectus, or more modern counterparts of ancient humans? As already noted, for various reasons, the initial conclusion was that these remains dated from a few million years ago. However, recent analytical work on sediment deposits from the burial cave indicates a much more recent date, implying that Homo naledi, a morphologically primitive hominin, survived into the later parts of the Pleistocene era (4). This extraordinary new dating brings the remains forward to a time when early humans were also present on the African savannah alongside this small-brained hominins, some 250,000 – 300,000 years ago:

“Scientists initially thought Homo naledi‘s anatomy suggested the fossils might be as much as 2.5 million years old and were startled by evidence that suggested the species may have buried its dead, a trait long believed to be uniquely human. But dating of the sediments in which the fossils were found and teeth of the specimens showed that the species was roaming the African bush between 236,000 and 335,000 years ago, around the time that modern humans were emerging.” (5)

How does this fit into the evolutionary lineages of modern humans? Lee Berger is convinced that these hominins represent an ancient track of the genus homo which managed to struggle through to the Middle Pleistocene era, getting way beyond their sell-by date in evolutionary terms. In other words, he thinks that that they’re an anomalous throw-back to a more ancient time:

“It is now evident that a diversity of hominin lineages existed in this region, with some divergent lineages contributing DNA to living humans and at least H. naledi representing a survivor from the earliest stages of diversification within Homo.” (6)

Whatever the truth may be about this assertion, what’s not in doubt is that Homo Naledi are giving palaeontologists a real headache. The remains represent a hybrid species of ancient hominin and modern human, brought together into a package that barely makes sense from any viewpoint:

We have a species which retains the capacity to move through tree-tops (as evidenced by the ape-like curvature of some of its finger bones), but yet is designed to move long distances across the savannah (which can be concluded from the human-like architecture of its legs and feet). Its pea-brained skull indicates a lack of capacity for higher level thinking, as provided by the remarkable expansion of the neocortex part of the human brain. This is, I would say, rather at odds with the hypothesis that an archaic hominin species had managed to survive a couple of million years within a fiercely competitive environment that it was not tailored to deal with.

So science is a bit stumped. What’s perhaps even more weird here is that the existence of Homo naledi sits remarkably well with the thinking of the late Zecharia Sitchin (7), whose ideas occupy the fringe ground of ancient alienism. Sitchin’s theory of the intentional genetic manipulation of hominin species – into an archaic human species capable of mining gold in Africa – combines well with the scientific evidence here, in at least three ways:

Sitchin’s argument was that the ‘intervention’ that created humanity took place about 300,000 years ago, in keeping with the timing discussed above;

This prototype ‘hybrid’ was clearly not the brightest spark on the prairie. To be able to move so deeply into such complex systems of caves implies the need for fire, which is a remarkable adaptation for hominins with such small brain sizes. This anomaly implies Homo naledi were in some way assisted, or instructed in the use of fire;

If Sitchin was right (and it would overturn the entire palaeontology bone-cart if he was) then Homo naledi, intriguingly called the ‘star man’ by scientists, represents one of the early experiments designed to create a malleable worker drone to service the gold mines of Africa. His use would have been limited, because he was, frankly, probably pretty stupid, and so eventually further genetic work came up with a far superior working model: Homo sapiens.

Other mysterious features of the South African landscape, highlighted by author Michael Tellinger, may fit in with these possibilities, as described in earlier blogs (8, 9). The widespread scattering of ancient corrals across the landscape of southern Africa implies an industrial scale level of activity, orchestrated in a highly organised manner.